gecko-dev/dom/localstorage/LSSnapshot.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_dom_localstorage_LSSnapshot_h
#define mozilla_dom_localstorage_LSSnapshot_h

namespace mozilla {
namespace dom {

class LSDatabase;
class LSNotifyInfo;
class LSSnapshotChild;
class LSSnapshotInitInfo;
class LSWriteInfo;

class LSSnapshot final
  : public nsIRunnable
{
public:
  enum class LoadState
  {
    Initial,
    Partial,
    AllOrderedKeys,
    AllUnorderedItems,
    AllOrderedItems,
    EndGuard
  };

private:
  RefPtr<LSSnapshot> mSelfRef;

  RefPtr<LSDatabase> mDatabase;

  nsCOMPtr<nsITimer> mTimer;

  LSSnapshotChild* mActor;

  nsTHashtable<nsStringHashKey> mLoadedItems;
  nsTHashtable<nsStringHashKey> mUnknownItems;
  nsDataHashtable<nsStringHashKey, nsString> mValues;
  nsTArray<LSWriteInfo> mWriteInfos;

  uint32_t mInitLength;
  uint32_t mLength;
  int64_t mExactUsage;
  int64_t mPeakUsage;

  LoadState mLoadState;

  bool mExplicit;
  bool mHasPendingStableStateCallback;
  bool mHasPendingTimerCallback;
  bool mDirty;

#ifdef DEBUG
  bool mInitialized;
  bool mSentFinish;
#endif

public:
  explicit LSSnapshot(LSDatabase* aDatabase);

  void
  AssertIsOnOwningThread() const
  {
    NS_ASSERT_OWNINGTHREAD(LSSnapshot);
  }

  void
  SetActor(LSSnapshotChild* aActor);

  void
  ClearActor()
  {
    AssertIsOnOwningThread();
    MOZ_ASSERT(mActor);

    mActor = nullptr;
  }

  bool
  Explicit() const
  {
    return mExplicit;
  }

  nsresult
  Init(const LSSnapshotInitInfo& aInitInfo,
       bool aExplicit);

  nsresult
  GetLength(uint32_t* aResult);

  nsresult
  GetKey(uint32_t aIndex,
         nsAString& aResult);

  nsresult
  GetItem(const nsAString& aKey,
          nsAString& aResult);

  nsresult
  GetKeys(nsTArray<nsString>& aKeys);

  nsresult
  SetItem(const nsAString& aKey,
          const nsAString& aValue,
          LSNotifyInfo& aNotifyInfo);

  nsresult
  RemoveItem(const nsAString& aKey,
             LSNotifyInfo& aNotifyInfo);

  nsresult
  Clear(LSNotifyInfo& aNotifyInfo);

  void
  MarkDirty();

  nsresult
  End();

private:
  ~LSSnapshot();

  void
  ScheduleStableStateCallback();

  void
  MaybeScheduleStableStateCallback();

  nsresult
  GetItemInternal(const nsAString& aKey,
                  const Optional<nsString>& aValue,
                  nsAString& aResult);

  nsresult
  EnsureAllKeys();

  nsresult
  UpdateUsage(int64_t aDelta);

  nsresult
  Checkpoint();

  nsresult
  Finish();

  void
  CancelTimer();

  static void
  TimerCallback(nsITimer* aTimer, void* aClosure);

  NS_DECL_ISUPPORTS
  NS_DECL_NSIRUNNABLE
};

} // namespace dom
} // namespace mozilla

#endif // mozilla_dom_localstorage_LSSnapshot_h